Validation of an Equine Smart Textile System for Heart Rate Variability: A Preliminary Study

Figures

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  Figure 1. The smart textile girth band system (Myant Inc., Skiin Equine). Light-blue squares indicate electrode positions.

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  Figure 2. ECG traces obtained using a smart textile device (Myant—top row) and a standard telemetric device (Televet—bottom row). ECGs were obtained simultaneously during (A) rest; (B) walk; (C) trot; (D) canter.

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  Figure 3. Correlation between two ECG devices (Myant, Televet) for mean HR at rest (A) and during exercise (B). Bland–Altman plots demonstrating the agreement between the two devices for mean HR at rest (C) and during exercise (D), where x-axes are the average of HR for each device, y-axes are the difference of Televet minus Myant HR, solid lines indicate bias, and dashed lines indicate 95% limits of agreement.

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  Figure 4. Bland–Altman plots demonstrating the agreement between the two devices for HR metrics at rest (A,C,E) and during exercise (B,D,F). SDRR = standard deviation of R-R intervals; HRV TI = heart rate variability triangular index; TIRR = triangular interpolation of the R-R interval histogram. X-axes are the average of each metric for each device; y-axes are the difference of Televet minus Myant for each metric. Solid lines indicate bias and dashed lines indicate 95% limits of agreement.

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  Figure 5. Bland-Altman plots demonstrating the agreement between the two devices for root mean square of successive R-R interval differences (RMSSD), at rest (A) and during exercise (B). X-axes are the average of RMSSD for each device; y-axes are the difference of Televet minus Myant RMSSD. Solid lines indicate bias and dashed lines indicate 95% limits of agreement.

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  Figure 6. Bland–Altman plots demonstrating the agreement between the two devices for nonlinear HRV parameters at rest (A,C) and during exercise (B,D). SD1 = Poincaré plot standard deviation perpendicular to the line of identity; SD2 = Poincaré plot standard deviation along the line of identity. X-axes are the average of SD1 or SD2 for each device; y-axes are the difference of Televet minus Myant SD1 or SD2. Solid lines indicate bias and dashed lines indicate 95% limits of agreement.